Cornell researchers: Vaporflys improve men's times by 2.1 to 4.1 minutes in marathon, women improve between 1.2 and 4 mins

I guess this stands true if both attempts between normal shoes and super shoes are done within a reasonable time frame. However, when comparing results annually, then there are simply too many factors to account for.

Setting aside the irrelevance of any other sport to the argument about the shoes - my previous point - I get your argument but you don't really address the point of just how much difference do the shoes make. Some here think it will be several minutes for top marathoners and yet I have seen studies (which I quoted earlier) that suggest the performance improvements will be marginal - and certainly not enough to ban them, as happened with brush spikes in the late-60's.

How much help do the new shoes give? Do they help some runners more than others? Are the shoes a quantum leap that will revolutionize running or are they not that much more of an advance than previous types of shoes were? I haven't seen anything definitive on that yet.

To many factors to argue about by following or comparing times from previous marathons, one race could have been in heavy rain and wind, the other in ideal conditions. A lab based study over a substantial period of time taking other factors like cadence, heart rate etc etc would be more accurate??

For what it's worth i think they do make a difference, i went from 2.52 to 2.43 in a year on same course, same conditions. Yes some of that time is probably due to better nutrition and training. But the biggest difference was definitely felt in my tiredness and efficiency.

They work

rojo wrote:

peekay wrote:

First of all, Rojo did you know that you were cited in the discussion section? Congratulations, you can put that on your CV when you go for academic promotion! Maybe you just started this thread to toot your own horn...

I had no idea. And the study is like several months old right? I was just doing the homepage one night and saw some referene to it and put it up. I was amazed their was a Cornell study that I didn't know about considering I spent 10 years of my life there but there isn't a lot of crossover between departments and what not at large schools like that.

Hell, one of the study's authors didn't even email us to put it up on the homepage and he's an LRC regular.

Good at statistics - very bad at marketing...

Armstronglivs wrote:

How much help do the new shoes give? Do they help some runners more than others? Are the shoes a quantum leap that will revolutionize running or are they not that much more of an advance than previous types of shoes were? I haven't seen anything definitive on that yet.

This is getting remedial, last post for me. I'm not sure what's missing here for you. Two clear parts to this

How much "help" do the new shoes give? The OG 4% was a lab tested running economy benefit of approximately 4% vs existing product in the Nike performance running range. This number came from their in-house testing and was verified by external labs. The Vaporfly/NXT% is greater than this number and so are other brands newer offerings (the adios pro). I know this because I have seen the results from further independent (to Nike) lab testing that validate this. When I say "lab" testing this is not mechanical testing of a shoe, it's V02max, running economy testing completed in a lab environment with real life human runners. You understand? Got it now? Do they help some runners more than others? Yes, but I don't understand how that is even relevant because the bottom line is, they help no matter what. In the same way that wearing a 150g gram shoe will give you a 1% performance benefit vs a 250g gram under equal conditions - a benefit is a benefit.

Are the shoes a quantum leap/much of an advancement? Well that's completely arbitrary. I don't know what counts as "quantum leap" for you. Some people think a day on the stock market up 1% is a big deal, others don't. At the end of the day it's for you to decide if you think 2-3 minutes at sub 2.05 marathon running is a quantum leap/much of an advancement or not. I think the fact we saw a human run under 2 hours for the marathon distance in product that was a large component of how it happened to be a substantial advancement. Aside from that we have a seen the womens and mens official marks obliterated and the number of sub 2.04 performances skyrocket in this era - so again, up to you if you think that's a quantum leap or not. Myself, other industry insiders and even non-industry experts such as Ross Tucker etc would rank this as a fairly substantial leap/advancement.

If multiple lab tests with published results (and some that aren't you would have to take my word for it) involving real runners and data sets of performances where the mean and outlier performances have all advanced substantially isn't definitive enough for you then all good my friend, you do you and continue living in that state of blissful ignorance. Not a bad thing either I guess.

I am more interested in real world performances than lab tests. I am not disputing the shoes are making a difference. The issue that matters for the sport is how much of a difference. Some views on this are conservative. So are you agreeing with this study - or not?

"The use of the Nike Vaporfly/Alphafly running shoes does not generate a historically unusual level of performance improvement when evaluating the world record improvements and when using a performance improvement index."[/quote]

"Does not generate a historically unusual level of performance improvement". That doesn't suggest such a big deal, does it?

Hi all,

I'm the author of that paper so if you have any questions, feel free to ask away. It was a deliberate intention to publish that paper in an open access format to encourage the kind of debate you have all been having in this thread so thanks for taking the time to do so. There have been many valid and important points.

For transparency, let me add some more of views on this topic:

1) The shoes technology are an effective design which definitely improve performance. The data is very clear on this and I support the other studies mentioned in this thread. My personal view is that such shoes though are a passive technology meaning they are only restorative (only able to return a fraction of the energy put into them) and are only an exercise in increasing efficiency really.

2) The reason so many people got upset about them was really because whilst they have seen a sudden uplift in running performance and access to them hasn't been equal for all. However, footwear design has been relatively stagnant and unchanged for decades and their potential impact completely underestimated. In short, many brands were either unwilling, unable or ignorant of pursuing such things. When you compare the impact of the shoes against other sports that utilise technology, their introduction is not unusual when looking at them in a general sports sense.

3) This technology is nowhere near being optimised. About 10 years ago, I was involved in research which looked at the Oscar Pistorius case and his use of prosthetic limbs in track running. We knew even back then that the spring had to be carefully matched to the step frequency and velocity of the runner to get the most from them. It's highly likely that shoes like the Vaporfly/Alphafly have been matched to their elite athletes and not club level runners. When a degree of customisation in the spring is created, you're going to get a lot more from such shoes.

Irrespective of whether we feel this is right or not, competitive sport is an arms race and running was merely just late to the party........ until now.

Best Wishes,

Dr Bryce Dyer

Armstronglivs wrote:

1) How much help do the new shoes give? Do they help some runners more than others?

2) Are the shoes a quantum leap that will revolutionize running or are they not that much more of an advance than previous types of shoes were? I haven't seen anything definitive on that yet.

1) To pick up on your excellent questions, the answer to these is going to be, 'it depends'. The main limitations of many of the studies being conducted is the participants used may or may not be good match's for the technology based upon the running velocity, their bodyweight and step frequency. To use an exaggerated analogy, think about how you gain height when using a trampoline - you use your bouncing to get in phase with the trampoline. To reduce your height, you work against this by taking yourself out of synchronicity with it (out of phase). If you can imagine doing that at a much smaller level with footwear, that shows you how that if the pebax and spring are fixed quantatities, how different runners may gain slightly more or less with such designs. I'm a 89kg ex-triathlete who is frankly not going to get the same response as a 65kg marathoner. However, tailor that response to each runner and then you've got a potential game changer.

2) The data does support a spike in performance increases and this is supported with the lab data. However, until such footwear is tailored more specifically to it's user, its too soon to say how much of a leap truly exists. However, Pandora's box is now open and don't believe that the new rules will limit things because what the brands have now discovered (if nothing else) is that serious R&D is now warranted in footwear beyond just that of gait management.

One of the best studies on Vaporfly I have seen!

Thank you for responding to my questions above.

If I understand you correctly it seems the effect of the shoes in performance will vary considerably, depending on the athlete. In this respect they appear different from the introduction of brush spikes in the late 60's, because the perceived advantage there was seen as being consistent and similar for those who used them - who were all sprinters.

However, the future you allude to is that there is the possibility of shoe technology being further developed that will offer considerable advantage to any level or style of runner, because the technologies may be better tailored to their user i.e. it won't be "one size fits" all, so to speak.

In the meantime I would be interested to know what is your assessment of the outer "trampoline effect" of the new shoes; in other words what do you think is the greatest potential performance gain that might be made by their use? I realise you say the data is not conclusive yet on that but I am sure you have a picture. Are we possibly seeing what amounts to "technological doping" by some athletes - albeit that is still legal?

More great questions. I'll try and answer them for you:

1) There is always a degree of response to any innovation (low responders, high responders, etc) for a variety of reasons but with your example of the brush spikes in particular, I'd generally agree with you. They both share the same overarching (and short term) issue though that an athlete sponsored by another brand and confounded by patents may not be able to access that same gain. If the marginal gain is still large enough, that issue can (and has been in other sports such as swimming) catastrophic and career affecting.

2) Yes, correct.

3) This is a tricky (if not impossible) one to answer. It's an incredibly complex effect. If we'd continued with multi-plates in those soles for example, it really would have made it very hard to predict but the level of tuning would have been superb. The shoes are actually quite crude and the gains on offer are still unexplored. To give you a bit of an idea, some of the prosthetic limbs at the paralympic games are tuned to benefit the athletes in different phases of a 100m/200m/400m race. You can't be fast at all of them but you set the limbs to benefit the runner when their impact is greatest. It's why you used to see Pistorius left in his blocks in the 100m only then to accelerate through the whole field in the final 10m (he would utilise that trampoline effect and hit a sweetspot when he hit a certain step frequency and velocity). Latter in his career he opted for stiffer limbs to get a better start (but the trade off was his finishing speed). Such effects are reduced in distance running whereby the variation in step cadence and running velocity don't vary that much but Nike shoes may also impact on fatigue resistance. The issue is that the study's are so few in number. The funny thing was that the press got hung up on the shoes sole thickness but the reason these shoes are so good was far more complex than just stack height.

4) I would say no. The reason is that this technology is only restorative in nature - it doesn't create additional energy in any way. It's merely improving the efficiency of what has historically been a poor level of energy return. However, if you ask me whether its fair, that's a far more subjective discussion and my paper aimed to highlight the breadth of such issues that exist beyond just asking whether the shoes are faster or not.

Just as an aside, some of us have attempted to compare advancements from one sport to another. Haake's 2009 study is a good example of this:

........and I've done similar with bits and pieces of my own work in the past too. Such values are purely discussion aids though rather than hard and fast values of stated performance improvements. I used such methods in my Nike paper really to try and encourage people to take a step back and see that when compared to other sports (or even running's own history), it's no less dramatic than other interventions in the past (that doesn't make it right, only to provide some context).

However, it may be more important to some people to try and minimise such leaps in performance to keep the sport relevant, keep its records historically comparable or just to ensure it remains all about human endeavour. I can completely understand that but if other sports are any indication, history suggests such aims are naive or doomed to fail.

Some of you may enjoy what other sports have had happen to them. If so, try another one of my reviews that looks at the controversy when it all goes wrong. Again, open access for anyone that is interested:

Thank you, sir. Appreciate your responses. Most interesting.

That's very helpful. Thanks.